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The brightest burst of light ever recorded was caused by a supernova, but that prompts new questions.

Astronomers detect long-sought compact object within the remnant of Supernova 1987A In February 1987, the closest supernova to Earth in almost 400 years exploded onto the scene. Designated Supernova 1987A (SN 1987A), it resulted from the death of a massive star in the Large Magellanic Cloud, a dwarf galaxy 160,000 light-years away. In the decades since, its remnant has been studied by telescopes at all wavelengths of light from X-rays to radio. Yet despite all the scrutiny, one mystery has remained.

A new way of interpreting the elusive mathematics of quantum mechanics could fundamentally change our understanding of reality.

By Karmela Padavic-Callaghan

This system consists of just 60 stars that are over 10 billion years old, all bound by their own gravity and maybe even dark matter, according to a press release from the W.M. Keck Observatory.

In physics, quintessence is a hypothetical form of dark energy, more precisely a scalar field, postulated as an explanation of the observation of an accelerating rate of expansion of the universe. The first example of this scenario was proposed by Ratra and Peebles (1988)^[1] and Wetterich (1988).^[2][3] The concept was expanded to more general types of time-varying dark energy, and the term “quintessence” was first introduced in a 1998 paper by Robert R. Caldwell, Rahul Dave and Paul Steinhardt.^[4] It has been proposed by some physicists to be a fifth fundamental force.^[5][6][7][8] Quintessence differs from the cosmological constant explanation of dark energy in that it is dynamic; that is, it changes over time, unlike the cosmological constant which, by definition, does not change. Quintessence can be either attractive or repulsive depending on the ratio of its kinetic and potential energy. Those working with this postulate believe that quintessence became repulsive about ten billion years ago, about 3.5 billion years after the Big Bang.^[9]

A group of researchers argued in 2021 that observations of the Hubble tension may imply that only quintessence models with a nonzero coupling constant are viable.^[10].

In this weeks continuation article of Dark Energy and what it is, we will be looking at Quintessence: which could be what dark matter is made of.

Quintessence. It is a “time-evolving and spatially dependent form of energy with negative pressure sufficient to drive the accelerating expansion” (Cladwell R.R. and Steinhardt P.J., 2000a, para 41).

Since it has negative pressure, it also has negative gravity. This negative gravity could explain the expansion of the universe. There are many models to describe quintessence, the simplest being, the fact that quintessence might be a quantum field with very long wavelength stretching across the universe. Negative gravity arises in this field by the negative pressure, and we can calculate the pressure by subtracting the Kinetic and Potential energies of the rate of oscillations in the field strength. This model is also successful, because it explains how the density of Dark Energy, or quintessence, changed over time, and fits in with the idea that dark energy must have been insignificant during the early universe to allow the large scale structures to form.

Analysis of the most precise three-dimensional map of the Universe delivers hints of a tension with the standard model of cosmology.

The majority of the matter in our Universe isn’t made of any of the particles in the Standard Model. Could the axion save the day?

As the infrared space telescope continues its long-duration survey of the universe, it is creating a unique resource for future astronomers to make new discoveries.

Continue reading “NASA’s NEOWISE Unveils Hidden Universe of Near-Earth Objects” »